Communication method and apparatus

Abstract

A communication method may be applied to a scenario in which a terminal is handed over from a source access network element to a target access network element, and the method includes: obtaining session information of a first session of the terminal, where the session information includes first service type information; obtaining first information, where the first information indicates service type information of local offloading supported by the target access network element; and if the target access network element supports local offloading of a service corresponding to the first service type information, determining that the target access network element processes the first session.

What is claimed is: 
     
       1. A communication method, applied to a scenario in which a terminal is handed over from a source access network element to a target access network element, and comprising:
 obtaining, by a first network element, session information of a first session of the terminal, wherein the session information comprises first service type information; 
 obtaining, by the first network element, first information, wherein the first information indicates service type information of local offloading supported by the target access network element; and 
 determining, based on the first information and the session information, that the target access network element supports local offloading of a service corresponding to the first service type information, and determining, by the first network element, that the target access network element processes the first session. 
 
     
     
       2. A communication method, applied to a scenario in which a terminal is handed over from a source access network element to a target access network element, and comprising:
 obtaining, by a first network element, session information of a first session of the terminal, wherein the session information comprises first service type information; 
 obtaining, by the first network element, first information, wherein the first information indicates service type information of local offloading supported by the target access network element; and 
 determining, based on the first information and the session information, that the target access network element does not support local offloading of a service corresponding to the first service type information, and determining, by the first network element, that a core network element processes the first session. 
 
     
     
       3. The method according to  claim 1 , wherein the first network element is the target access network element, and the first session is a session managed and controlled by the source access network element before the terminal is handed over. 
     
     
       4. The method according to  claim 3 , wherein that the target access network element obtains the session information of the first session of the terminal comprises:
 receiving, by the target access network element, the session information from the source access network element or a core network element. 
 
     
     
       5. The method according to  claim 3 , wherein after the target access network element determines that the target access network element processes the first session, the method further comprises:
 updating, by the target access network element, the session information of the first session. 
 
     
     
       6. The method according to  claim 5 , wherein the updating, by the target access network element, the session information of the first session comprises:
 allocating, by the target access network element, a new internet protocol (IP) address to the first session, and updating the session information based on the new IP address; and 
 sending, by the target access network element, the new IP address to the source access network element, the terminal, or a core network element. 
 
     
     
       7. The method according to  claim 6 , wherein the method further comprises:
 sending, by the target access network element, a first indication to the source access network element, wherein the first indication indicates that the new IP address has been allocated to the first session. 
 
     
     
       8. The method according to  claim 3 , wherein the method further comprises:
 performing, by the target access network element, address resolution protocol (ARP) route update on an IP address of the first session. 
 
     
     
       9. The method according to  claim 3 , wherein the method further comprises:
 determining, based on the first information and the session information, that the target access network element does not support the local offloading of the service corresponding to the first service type information, and determining, by the target access network element, that a core network element processes the first session; and 
 sending, by the target access network element, the session information and access network tunnel information of the first session to the core network element. 
 
     
     
       10. The method according to  claim 1 , wherein the first network element is a core network element, and the first session is a session managed and controlled by the source access network element before the terminal is handed over. 
     
     
       11. The method according to  claim 10 , wherein that the core network element obtains the session information of the first session of the terminal comprises:
 receiving, by the core network element, the session information from the source access network element. 
 
     
     
       12. The method according to  claim 1 , wherein the first network element is a core network element, and the first session is a session managed and controlled by the core network element before the terminal is handed over. 
     
     
       13. The method according to  claim 12 , wherein after the core network element determines that the target access network element processes the first session, the method further comprises:
 sending, by the core network element, the session information to the target access network element. 
 
     
     
       14. The method according to  claim 10 , wherein the method further comprises:
 receiving, by the core network element, a new internet protocol (IP) address of the first session from the target access network element; and 
 sending, by the core network element, the new IP address of the first session to the terminal. 
 
     
     
       15. The method according to  claim 14 , wherein the method further comprises:
 receiving, by the core network element, a first indication from the target access network element, wherein the first indication indicates that the new IP address has been allocated to the first session; and 
 sending, by the core network element, validity time of an old IP address of the first session to the terminal according to the first indication. 
 
     
     
       16. The method according to  claim 2 , wherein the method further comprises:
 receiving, by the first network element, a new internet protocol (IP) address of the first session from the core network element; and 
 sending, by the first network element, the new IP address of the first session to the terminal. 
 
     
     
       17. The method according to  claim 1 , wherein the first information and the first service type information each comprise at least one piece of the following service type identification information:
 network slice selection assistance information (NSSAI); 
 a data network name (DNN); or 
 an application identifier (App ID). 
 
     
     
       18. The method according to  claim 17 , wherein the first information further comprises a local support indication, and the local support indication indicates that the target access network element supports local offloading of a service corresponding to the service type identification information. 
     
     
       19. The method according to  claim 17 , wherein the determining, based on the first information and the session information, that the target access network element supports local offloading of a service corresponding to the first service type information comprises:
 in response to the first service type information matching the service type information that is of the local offloading supported by the target access network element and that is indicated by the first information, determining, by the first network element, that the target access network element supports the local offloading of the service corresponding to the first service type information, and determining, by the first network element, that the target access network element processes the first session. 
 
     
     
       20. A communication apparatus, wherein the apparatus is used in a target access network element, applied in a scenario in which a terminal is handed over from a source access network element to the target access network element, and comprises a processor, wherein the processor is configured to:
 obtain session information of a first session of the terminal, wherein the session information comprises first service type information; 
 obtain first information, wherein the first information indicates service type information of local offloading supported by the target access network element; and 
 determine based on the first information and the session information, that the target access network element does not support local offloading of a service corresponding to the first service type information, and determine that a core network element processes the first session.